/Engine/Source/Runtime/Core/Public/Containers/Set.h
int32 FindIndexByHash ( const void * Element, const [FScriptSetLayout](API\Runtime\Core\Containers\FScriptSetLayout) & Layout, uint32 KeyHash, [TFunctionRef](API\Runtime\Core\GenericPlatform\TFunctionRef)< bool(const void *, const void *)> EqualityFn )